The manufacture of wireless communication devices, which include any type of device that can communicate over a wireless communication network, is commonly subsidized by a network access provider such as Sprint, Verizon, AT&T Mobile, and others (also referred to herein as “carriers”). When a wireless communication device (also referred to herein as a “wireless device” “handset” or “mobile device”) is manufactured, it is usually programmed and provisioned. Alternatively, a wireless communication device may be programmed and provisioned when it is activated by a carrier.
The programming and provisioning (referred to herein collectively as “programming”) of a wireless communication device provides the handset with its profile. The handset profile includes its telephone number (also referred to herein as “machine identification number” or “MIN”), its area code (also referred to herein as “MIN2”), as well as other operating parameters, network parameters, and application software. These items are placed in persistent memory on the handset where they cannot be modified or deleted without authorization.
Use of a handset on a particular carrier's network can be governed by the area code that is assigned to the handset. In conventional handsets, the area code can be modified to allow the handset to be used on another carrier's network. This ability to modify a handset for use on a network other than the network of the carrier who subsidized the manufacture of the handset provides a disincentive to the carrier to subsidize and in turn drives up the cost of handsets to consumers.
Therefore, what is needed is a system and method that provides additional security in handsets against unauthorized modifications to the area code or the table of valid area codes.